Drug Target Review – Katheryn Begg and Mahvash Tavassoli – Since the sequence of the human genome was published some 20 years ago, omics strategies have enabled the generation of detailed molecular signatures of cancers and their subtypes.
This new information has spurred efforts towards stratification of patients bearing those signatures, development of targeted therapies, and has opened up the paradigm of precision medicine – by using biomarkers. However, the inherent complexity and ever-shifting genetic landscape of cancer has seen many targeted therapies become provocateurs of treatment-induced phenotypes and acquired resistance. Even promising biomarkers that have been identified in attempts to bypass this harbour issues concerning translation and implication into the clinic. Yet there is hope. Evidence from the successful use of biomarkers for diagnosis, screening and management of cancers such as breast and prostate has resulted in earlier diagnoses, higher survival and lower morbidity rates, thus validating the clinical relevance of this concept. Additionally, research into new biomarkers such as PD-1 and CTLA4, and new biomarker classes such as microRNAs and exosomes, coupled with the promise of stronger connections between the realms of molecular biology and biotechnology, means that the new era of biomarker discovery for precision medicine in cancer begins now.